Improvement in heating and feeding air to furnaces



-2 Sheets-Sheet Z.

J. FERGUSoN. Y HEATING AND FEEDING AIR T0 FURNACES.

No.184,361. P nnnnn ea,Nov.14,1a7`s.

'forced or directed against the boiler.

UNITED STATES PATENT Cri-rca JOHN FERGUSON, OF PITTSBURG, PENNSYLVANIA.

IMPRovEMENT iN HEATING AND FEEDING AIR To FuRNAcEs.

Specification forming p art of Letters Patent No. 184,361,datedpNovember 14, 1876; application filed September 1, 1876. l

To all 'whom it may concern:

Be it known that I, JOHN FERGUSON, of

'-Pittsburg, in the countyof Allegheny and State of Pennsylvania, haveinvented certain new and useful Improvements in Furnaces; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit pertains to make and use it, reference being` had to the accompanyingdrawings, which form part of this speciiication, in which- Figure l is alongitudinal vertical section. Fig. 2 is a horizontal section throughfines c. Fig. 3 is a horizontal section through ues c. Fig. 4 isatransverse section on line .fc a'. Fig. 5 is a transverse section online a," zr. Fig. 6 is a detail. Fig. 7, another. Fig. 8 shows tlues cdipping vertically.

This invention relates to furnaces of that class in which the productsof primary combustion are mingled with highly-heated atmospheric air, toform an inflammable gas, which is ignited by the flames and consumed;and consists in the arrangement and combination of parts, as hereinafterfully described and claimed.

In the drawings I illustrate my invention as applied to a steam-boiler,A, which in'this case is of the dome-headed construction, but may be ofany other kind. B is the combustion chamber, at or about the end of theboiler. At the inner end of this chamber I erect a hollow bridge, O,having its rear wall perforated, asin Fig. 5.V Beyond this bridge,starting from the surface of the boiler, is a hanging bridge, D, whoselower edge dips below the level of the lowest perforations in bridge C.This construction causes the flames and smoke or gases to dive down andup, as indicated by the arrows in spaces t and k thence up over thesolid bridge e, so as to be Then it passes along the open space a underthe boiler, turns upward through a, and passes around the boiler,through fine b, to the smokestack. As this encircling-line b is no partof the present invention, I need not describe it further, or allude toit in any way.

Entering from the front of furnace or thereabout, and passing throughits containingthe bridge c the flues c c diverge laterally,

asin Fig. 3, or vertically as in Fig. 8, then pass along parallel totheir former direction, still toward the front, till they reach a pointlaterally or vertically in line with the hollow bridge C, into whichthey then immerge. The

specific arrangement of these fines forms the chief part of myinvention. The air receives heat from the very moment of its entrance,because the flue passes along the walls of the combustion-chamber; and,throughout the length of the air-hues, air is in almost immediatecontact with the flames, separated by onlyafewinches at every point.Hence, there must be a constant accession to the air of the radiatedheat, and the heat increases constantly up to the very point wheretheair should be hottest-viz., whereit emerges from the hollow bridge intothe space i. In fact, I have succeeded in bringing the air to suchdegree of heat that it sufficed to melt zinc, requiring a temperature ofno less the 6000 Fahrenheit. The air, thus highly heated,

passes through'the rear of bridge C, strikes into, and is intimatelymingled with,the gases of combustion in space i. The consequence is, theheated oxygen feeds the gases until they ignite and produce an intenseheat, which is then carried upward to heat the boiler. The boiler isthus heated by an intenselyhot ame which produces no smoke, andtherefore no carbon or soot is deposited on the boiler to form anon-conducting surface. Thus I utilize a large amount of the heatactually produced, but wasted, under ordinary circumstances; and I doaway with the necessity of cleaning surfaces, while at the same time Ieffect complete combustion of the fuel productsand thereby add largelyto the heat first developed by the initial consumption of the fuel. Theresult is, intense steam is formed for use in a short space of time, andthe furnace consumes but little fuel.

The characteristic of myinvention is in combining simplicity ofconstruction With such arrangement of air-fines, With relation to thetire-space, as shall effect aconstant steady increase in the temperatureof the incoming air from its first entrance up to the point Where it isutilizedso that at no time in its passage shall it suffer cooling, or astand-still in temperature.

Having thus described my invention, what I claim as my invention is- Thecombination of the fines c and c/arranged substantially as described,with the hollow bridge C, having its rear surface perforatedfor theadmission of air to the main ilue, substantially as specified.

In testimony that I claim the foregoing, I have hereunto set my handthis 29th day of August, 1876.

" JOHN FERGUSON.

Witnesses:

PHILIP ARBoGAsT, THos. J. MCTIGHE.

